The role of humerus cortical thickness in predicting osteoporosis in MR imaging.

Aim: This study aims to evaluate the efficacy of humerus cortical thickness on coronal T1-weighted images of the humerus in distinguishing patients with normal vs. abnormal bone mineral density (BMD).

Methods: Patients (n:138) with shoulder magnetic resonance imaging (MRI) and dual-energy x-ray absorptiometry (DXA) scans were evaluated. Patients were grouped into normal and low BMD (osteopenia and osteoporosis) according to DXA. An average cortical bone thickness (CBTavg) and gauge cortical bone thickness (CBTg) were calculated from the proximal humerus on coronal T1W MRI. Sensitivity and specificity for the prediction of osteoporosis were determined for several cortical bone thickness thresholds.

Results: Proximal humerus average cortical bone thickness measurements strongly correlated with DXA femur and lumbar scores (p < 0.01). Gauge cortical thickness measurements also correlated with DXA femur and lumbar scores (p < 0.01). Average cortical bone thickness measurement of 4.52 mm was determined to be a potential marker for predicting osteoporosis, with a sensitivity of 92.3% and a specificity of 84.9%.

Conclusion: Average cortical bone thickness measurements obtained from shoulder MRI are correlated with DXA. It appears to be effective in differentiating patients with normal and abnormal BMD and may help to opportunistically predict patients with osteoporosis in a rapid, simple and practical way, potentially guiding further diagnostic assessments.